Airflow Meter
Airflow meter measures the amount of air aspirated and provides a signal to the control unit. The aspirated air applies force to the flap so that its opening angle is balanced with the return torque of the helical spring. The flap shaft is connected to a potentiometer, which corresponding with its opening angle, provides a voltage signal to the control unit.
After engine start-up, a set of contacts are closed to signal fuel pump operation. See Fig 1.